We are looking to buy a small & light motorbike. Usually Chinese brands, gas-engine. Need to be light enough to be carried on a yacht.

Any shops around Royal Phuket Marina? Thank you all. MS>

Might be worth asking at the chandlers almost opposite the main entrance to Boat Lagoon.   They have quite extensive spares as well as outboards, dinghys, canoes etc.   Though they might not have what your looking for, they may know where you can get it.